As of today, I've spent more than 11 years in Guantánamo Bay. To be precise, it's been 4,084 long days and nights. I've never been charged with any crime. I've never been allowed to see the evidence that the US once pretended they had against me. It's all secret, even the statements they tortured out of me.

In 2007, roughly halfway through my ordeal, I was cleared for release by the Bush administration. In 2009, under Obama, all six of the US frontline intelligence agencies combined to clear me again. But I'm still here.

Every day in Guantánamo is torture – as was the time they held me before that, in Bagram and Kandahar air force bases, in Afghanistan. It's not really the individual acts of abuse (the strappado – that's the process refined by the Spanish Inquisition where they hang you from your wrists so your shoulders begin to dislocate, the sleep deprivation, and the kicks and punches); it's the combined experience. My favourite book here (I've read it over and over) has been Nineteen Eighty-Four by George Orwell: torture is for torture, and the system is for the system.

More than a decade of my life has been stolen from me, for no good reason. I resent that; of course I do. I have missed the birth of my youngest son, and some of the most wonderful years with all my four children. I love being a father, and I always worked to do it as best I can.

So obviously I want to go home to London. Of course I do. But I am never going to beg. If I have to die here, I want my children to know that I died for a principle, without bowing to my abusers. I have been on hunger strike for more than 60 days now. I have lost nearly a quarter of my body weight. I barely notice all of my medical ailments any more – the back pain from the beatings I have taken, the rheumatism from the frigid air conditioning, the asthma exacerbated by the toxic sprays they use to abuse us. There is an endless list. And now, 24/7 (as the Americans say), I have the ache of hunger.

Have you ever tried going without food for 24 hours? Today, I am on my 68th day. But a man in my block has been on strike since 2005. Can you imagine it? He's only alive today because the Americans force-feed him, preventing him from making that ultimate statement of principle, the same one they have on their New Hampshire licence plates: "Give me freedom, or give me death."

In truth, while I am horrified by the suffering around me, I am also encouraged. There is more solidarity among the prisoners than ever before. The military is not being honest about the number of men on strike: most of us are refusing to eat. The military responds with violence, as if that will break us; it draws us all together.

Now they are sending in the goon squad (the Forcible Cell Extraction, or FCE, team) to beat me up every time I ask for something, whether it is my medicine, a bottle of water or the right to shower. That only reinforces my resolve. And my lawyer tells me there are people out there who care, that more than 100,000 people back home in Britain have signed a petition demanding that parliament should debate my case.

I hope I do not die in this awful place. I want to hug my children and watch them as they grow. But if it is God's will that I should die here, I want to die with dignity. I hope, if the worst comes to the worst, that my children will understand that I cared for the rights of those suffering around me almost as much as I care for them.